yellowing leafs please help!

I currently have 2 plants both about 5 weeks old and about 8/9 inches high.
recently the lower leaves started to turn yellow, and they are getting yellower.
Ive looked through some posts and think it may be nitrogen deficincy. I am feeding them Ionic grow.
Ive read here that you should water whe them when the top 3/4 inches of soil gets dry, however mine is constantly dry, and when i water the leafs start drooping and then im scared to water them anymore!
Could this be a water deficency? they were growing well untill about a week ago, now their not showing much signs of growth allthough new leafs are developing on the branches.
Any ideas? Ill upload a picture
thanks

those could have been reciving more nutes if they r five weeks old bro, and the reason the leaves are getting droopy after you water is because you are watering them too much try to get on a schedule with your watering water with nutes one feeding then check the next day stick your finger down there if you can got to your nuckle the first one water with plain ewater and so on up the nutes whats the npk value of the nutes you are usin?

Ive just found out im using hydroponics neutrients. I have a hydroponics system, but i cant use it becasue plans changed.
Here is the link to the neutrients im using http://growthtechnology.com/nute-ionic-hydro.asp
i have some baby bio but i havent used that, the back of the neutrients says to use 7ml per litre, but ive been doing about 2.5 for now, and was going to bring it up later. my book says i should aim for 12-14 on the neutrient meter for now, and ive been aiming for that.
Is the plant not as big as it should be for a 5 week old plant?
cheers

nah shuld be a bit more bushier bro here click on the link in my journal the last link and there are two plants tha are about the same age of mine

too much water

Ah now im more worried! i do like your grow journal, and i will alternate when i add neutrients to the water. What Cf level should i be aiming for?
And as for pitballs, im more of a staffordshire bull terrior man myself, i have 2 Pitballs are banned over here in the uk.

peeping pooh said:

Ah now im more worried! i do like your grow journal, and i will alternate when i add neutrients to the water. What Cf level should i be aiming for?
And as for pitballs, im more of a staffordshire bull terrior man myself, i have 2 Pitballs are banned over here in the uk.

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well grab bout 3 or 4 150 watt replacement cfls and you will be suprised. and as for bull terriers i have a friend an hous who has been breeding spud mckanzie dogs for years man they r great dogs but i love my pits